Distribution valves are known in the art and have been used in both irrigation and wastewater treatment systems to allow fluid to be effectively distributed over large areas. One common mechanical liquid distribution valve (MLDV) is manufactured by K-Rain Corporation of Florida. This MLDV includes an enclosure having a single inlet and a plurality of outlets, typically four (4), five (5) or six (6). A plunger is centrally disposed within the enclosure and is secured to a rubber plate that can be moved to seat against the valve bottom. The plate has an aperture therein that aligns with one of the outlets. The plunger accommodates a spring element that acts on the plate to force it away from valve bottom. When fluid under pressure is supplied to the inlet, the force of the fluid moves the plunger down through a cam causing the plunger and plate to rotate and seat the plate against the valve bottom with the aperture in the plate in alignment with one of the outlets. When the fluid pressure supplied to the inlet drops, the plate and plunger are biased back upwardly thereby moving the plunger back through the cam and causing the plunger and plate to rotate. When fluid under pressure is again supplied to the inlet, the plunger and plate move downwardly against the spring bias and rotate thereby to seat the plate against the valve bottom with the aperture in the plate in alignment with the next outlet. Cycling fluid pressure to the MLDV in this manner therefore allows the incoming fluid to be distributed to the outlets of the MLDV in succession.
FIG. 1 shows a conventional arrangement for an MLDV 10. As can be seen, the MLDV 10 includes an inlet 12 connected to a pump 14 via a conduit 16. The pump 14 draws fluid from a fluid source such as a reservoir or tank 18 via a conduit 20. The pump 14 is operated to cyclically supply fluid under pressure to the inlet 12 of the MLDV 10 at intervals. The outlets 24 of the MLDV 10 are connected to a plurality of discharge points 26 positioned at different zones by conduits 28. During typical operation, the MLDV 10 couples the outlets 24 to the inlet 12 in succession so that fluid flow to the discharge points 26 cycles through a desired pattern allowing the fluid to be effectively distributed.
Although MLDVs serve a valuable and useful purpose, they are subject to failure and/or improper operation. Over time, MLDVs can be worn resulting in failure. Rocks or other debris may become lodged in the MLDV internal mechanisms thereby preventing the MLDVs from moving through their cycles. Installation errors may also result in improper MLDV operation. Furthermore, sub-optimal pump timing, freezing, insufficient fluid flow or inadequate fluid pressure and/or air in the conduits may result in inconsistent MLDV operation and skipping.
Regardless of the environment in which MLDVs are being used, it is important for the MLDVs to operate properly so that fluid is applied uniformly throughout the various zones. Failure to do so can be problematic. In irrigation systems, failure of MLDVs may result in zones being supplied with excess or insufficient water. In farming environments, excess water in any particular zone may reduce crop yields due to leaching of plant nutrients, increase disease incidence and/or fail to stimulate growth of commercially valuable parts of crops. Insufficient watering in any particular zone may lead to high soil moisture tension that creates plant stress and reduces crop yield. In other environments such as for example on golf courses where MLDVs are used to distribute water to greens, failure or skipping of the MLDVs may result in extensive damage.
When used in wastewater treatment and/or disposal systems, failure of MLDVs is of even more concern due to the potential environmental impact resulting from such a failure. Even distribution of treated effluent across dispersal zones is essential to ensure that the treated effluent is naturally absorbed into the environment. In wastewater treatment systems employing filter media such as for example, soils, textile filters etc., if the filter media is overloaded, its ability to treat effluent may be adversely affected potentially resulting in serious environmental problems including groundwater contamination and surfacing/breakout of untreated effluent.
Unfortunately, to-date there has been no convenient way of determining whether MLDVs are operating properly. Presently, in order to determine proper MLDV operation, it is necessary to visually inspect each MLDV. During inspection, the system must be partially dismantled so that the MLDV can be cycled by manually turning the inlet fluid pressure on and off and visually monitoring the fluid output of the MLDV. As will be appreciated, inspecting MLDVs in this manner is time consuming and impractical especially in systems employing significant numbers of MLDVs. As a result, there is a need for improved methods of monitoring MLDV operation.
It is therefore an object of the present invention to provide a novel distribution valve monitor and a novel distribution valve incorporating the same.